Fig. 16. Sensory supply to the orbit. Parasagittal view shows the trigeminal nerve branches of the ophthalmic division (opn): ncn, nasociliary nerve; ln, lacrimal nerve; fn, frontal nerve; stn, supratrochlear nerve; son, supraorbital nerve; shown but not labeled: long ciliary nerve, anterior ethmoidal nerve. Branches of the maxillary division (mxn) are also shown: ion, infraorbital nerve; zyn, zygomatic nerve; ana, anastamosis with lacrimal nerve; zfn, zygomaticofacial nerve; ztn, zygomaticofrontal nerve. Note the sympathetic chain webbed around the carotid siphon. Gg, geniculate ganglion; mnn, mandibular division; pg, pterygoid (sphenopalatine) ganglion; abn, abducens nerve; trn, trochlear nerve; ocn, oculomotor nerve. (Modified from Rootman J, Stewart B, Goldberg RA: Orbital Surgery: A conceptual Approach, p. 117. Philadelphia, Lippincott-Raven, 1995)